L.E.D lighting

kill9

kill9

Active Member
I haven't seen a setup of LEDS that flowered marijuana.

Although it is great for vegetation, but I think it needs more wattage for big beautiful flowers.

Alot of people saying LED sucks, etc. How bout you try them or actually have an educated opinion instead of saying "LED sucks". You stoners embarass me.
 
Detchord

Detchord

Active Member
I Have been using LED's for over a year now. I love em! THEY WORK! I have never had happier plants. They love the led light. Veg is incredibly fast! Flowering I get as big or bigger flowers in a shorter time, typically the whole grow is 2-3 weeks faster. No joke! I go from rooted cuttings to flower in 2-3 weeks, and full bloom another 4 weeks after that.
 
dazed&confused

dazed&confused

Active Member
I was reading that LED LIGHTING IS EFFECTIVE IN THE EARLY STAGES OF THE PLANTS GROWTH, VEGGIES AND SEEDLING STAGES BUT POOR IN THE FLOWERING STAGE
 
dazed&confused

dazed&confused

Active Member
Hey detchord do you have images of your set up? I am interested in an led set up for my grow, do you have any online sources of where to order a good quality lighting system. Thanks
 
4

40acres

New Member
kill9 said:
I haven't seen a setup of LEDS that flowered marijuana.

Although it is great for vegetation, but I think it needs more wattage for big beautiful flowers.

Alot of people saying LED sucks, etc. How bout you try them or actually have an educated opinion instead of saying "LED sucks". You stoners embarass me.
Click to expand...
Thunderchunkie did a complete grow with led's.THey sucked salty balls. Search for it and then come back. Thanks.
 
T

techhead420

Well-Known Member
Detchord said:
I Have been using LED's for over a year now. I love em! THEY WORK! I have never had happier plants. They love the led light. Veg is incredibly fast! Flowering I get as big or bigger flowers in a shorter time, typically the whole grow is 2-3 weeks faster. No joke! I go from rooted cuttings to flower in 2-3 weeks, and full bloom another 4 weeks after that.
Click to expand...
BS. What do you have to sell? The only people who hype this fraud like you just did of a light seem to have something to sell. It's suspicious that this is your first post....

LEDs are less efficient and have a lower luminous efficacy than any HID style lighting. The lower luminous efficacy should be a hint right there that and this point of technology they can not compete with HPS. Give them 5 years.

The spectral absorbtion graphs that LED grow light manafactuers are also misleading BS; they focus on absorbtion characteristics of molecules (chlorophyll etc) rather then look at the actual uptake of carbon dioxide (which shows true growth).

I have about 120 watts worth of LED lighting (including 15 watt LEDs) and after a year of using them I can say with confidence that they are the worst light for flowering. Even in side by side testing in the veg stage I found that CFLs are going to out perform LEDs watt for watt.

Save your money people, don't buy into the complete BS hype that the LED grow light manufactuers are spewing out.
 
The Martian

The Martian

Active Member
Hi All.
This is my first post, I haven't grown for a number of years, (quite a number), and have just put in a batch of seeds, thought I'd give her another go.
Anyone wishing to grow indoors would have to be blind not to have seen the blurb about LED growing, and while the promise is there, it seems actual results are sparse.
But I believe the time is here/coming very soon, not 5 years.
The last post I feel is wrong in a couple of areas.
LEDs of late have surpased the efficiency of compact flouro's, but I dont think full tubes yet, but getting there.
The absorbtion graphs are correct, a plant is green and so reflects any green light falling on it, hence it cannot use what is not absorbed, and the reason a Sodium or M Halide looks so bright to us is because they was originally desighned for us to see, for lighting, and although they have adjusted the phosphors, to diminish the middle of the visible spectrum, and push it to either end, (red and blue) none the less, they still produce a prodigious amount of light right in the middle, where it is almost all wasted.
So although these lamps look reasuringly bright to us, to a plant they look much less bright. Just go look at an absorbtion graph, and a human eye response graph, the curves couldn't be any more opposite.
And your " CO2 uptake" theory is spuriouse, if it cannot photosinthesise it cannot convert CO2 to plant mass whatever the reason.
Could you be a bit more specific about your experience, you say you have 120 Watts of LEDs, what kind/size/output, how many, Colours, ratio of colours.
How far off plants, and grow area.
when you say 15 watters, are you talking about a 15 watt LED, or lamp/array. Ive not come accross 15 watt LEDs yet.

I beleive poeple are trying to spread things too thinly, vegging when smaller one will get away with it but as they get bigger the distance between top and bottom gets bigger, and as we know this affects things badly, don't forget light, (from a point source at least) follows the inverse square law, so moving a light from 6 inches to 12 inches, the light doesn't half, it quarters, (as near as dammit), move it another 6 inches, your now one ninth the original intensity.
I am just starting building my new settup, and I intend building myself a new Led vegging light, to bring cuttings seedlings up to flowering stage,
but even for this I'll be using 30 3 watt high power Leds probably 20 red 10 blue.
I will be testing this against the 3 x 4 foot flouro tube (normal tubes, one cool two warm, can't remember the actual col temps off hand) vegging light I made years ago, if this works out I intend building, myself two, flowering lights, to go either side of a 400 watt M Halide/sodium light.
Each light will be built of 60 Red 10 Blue 3 watt high power Leds.
with this set up I will be trying to see how much I can grow in, I'm hoping for over 2.5 square meters, but well see.
I see lots of talk out there and poeple trying to flower 2 Square Metres, of 3 foot high plants with 250 0r 500 so called high intensity LED panels, two foot from the plants and then they wonder why it turns out crap.
Granted this is still in its infancy, and to buy built up lamps is still very expensive, anything remotely powerfull anyway.
But they are getting better month by month, and very soon LEDs will be replacing HIDs in lighting applications, street lights even.
The time is now, or very soon Ha Ha Ha.
The plusses especially for weed, are numerous, and soon someone other than NASA, will make it work.
Hope its me!!!!!!!!!!!!
I'll keep you all informed of anything interesting.
Sorry if I went on a bit.
The Martian
 
mane2008

mane2008

Well-Known Member
Mane fuck dem L.E.D. light either cfl, hps, MH, sun or dont even think about it.

Purple lights?
Bra put them girly chirstmas lights away.
 
mane2008

mane2008

Well-Known Member
Detchord said:
I Have been using LED's for over a year now. I love em! THEY WORK! I have never had happier plants. They love the led light. Veg is incredibly fast! Flowering I get as big or bigger flowers in a shorter time, typically the whole grow is 2-3 weeks faster. No joke! I go from rooted cuttings to flower in 2-3 weeks, and full bloom another 4 weeks after that.
Click to expand...
I bet my MH grown plants outdid ya christmas light plants
 
The Martian

The Martian

Active Member
HI there again.
BTW, Im am not affiliated with anyone, and I'm NOT trying to sell anything.
Yet anyway;-)
Ha Ha Ha Ha

Yours The Martian
 
The Martian

The Martian

Active Member
Hi All
As Mane2008 says;
"Purple lights?
Bra put them girly chirstmas lights away."

While talking from complete ignorance, hits on a salient point, this is what a lot of the faliures are down to in my opinion, poeple using poxi old low output cheapo LEDS, a thousand of these would still be useless, how many have used Good quality modern high output LEDs in reasonable numbers????
these LEDs are not cheap, even the 5mm ones, red 14000 mcd, 20 deg (around 1.5 -2 lumen) 20ma, are around £28 for 100 £190 for 1000.
So its no wonder poeple have tried with "christmas tree lights".
One can get lower output ones cheaper of course, but the numbers needed then become prohibitive, (as if they arn't allready).
Has anyone tried any of the quality lights, the ones that use 50 odd or so of the Cree High output LEDs, and in a reasonable sized area?
BTW one of the comparison grow vids, I saw put a 90 watt LED array up against I think a 400 watt sodium, and got pretty crap results. but the guy left the LED lamp way high up, as high up as the HID lamp, I wonder what would have happened had he positioned the lamp as close as is safe from the plant?
As it was the yeild was only about a third of that of the HID system.
Much more testing needs to be done, but with more realistic LED light levels.
Think about it though, it LOOKS like much less light, no (well much less) infra red heat signiture, lower power consumpion, even half or third would be smashing, with electricity about to go up by another 60%.
No need for new lamps every 6-12-18 month, depending on what you read.
It really is all down hill once the light has been purchased, but its up to us to build the shit and find out.
Ta Ta till next time
The Martian
 
T

techhead420

Well-Known Member
The Martian said:
Hi All.
This is my first post, I haven't grown for a number of years, (quite a number), and have just put in a batch of seeds, thought I'd give her another go.
Anyone wishing to grow indoors would have to be blind not to have seen the blurb about LED growing, and while the promise is there, it seems actual results are sparse.
But I believe the time is here/coming very soon, not 5 years.
The last post I feel is wrong in a couple of areas.
LEDs of late have surpased the efficiency of compact flouro's, but I dont think full tubes yet, but getting there.
The absorbtion graphs are correct, a plant is green and so reflects any green light falling on it, hence it cannot use what is not absorbed, and the reason a Sodium or M Halide looks so bright to us is because they was originally desighned for us to see, for lighting, and although they have adjusted the phosphors, to diminish the middle of the visible spectrum, and push it to either end, (red and blue) none the less, they still produce a prodigious amount of light right in the middle, where it is almost all wasted.
So although these lamps look reasuringly bright to us, to a plant they look much less bright. Just go look at an absorbtion graph, and a human eye response graph, the curves couldn't be any more opposite.
And your " CO2 uptake" theory is spuriouse, if it cannot photosinthesise it cannot convert CO2 to plant mass whatever the reason.
Could you be a bit more specific about your experience, you say you have 120 Watts of LEDs, what kind/size/output, how many, Colours, ratio of colours.
How far off plants, and grow area.
when you say 15 watters, are you talking about a 15 watt LED, or lamp/array. Ive not come accross 15 watt LEDs yet.

I beleive poeple are trying to spread things too thinly, vegging when smaller one will get away with it but as they get bigger the distance between top and bottom gets bigger, and as we know this affects things badly, don't forget light, (from a point source at least) follows the inverse square law, so moving a light from 6 inches to 12 inches, the light doesn't half, it quarters, (as near as dammit), move it another 6 inches, your now one ninth the original intensity.
I am just starting building my new settup, and I intend building myself a new Led vegging light, to bring cuttings seedlings up to flowering stage,
but even for this I'll be using 30 3 watt high power Leds probably 20 red 10 blue.
I will be testing this against the 3 x 4 foot flouro tube (normal tubes, one cool two warm, can't remember the actual col temps off hand) vegging light I made years ago, if this works out I intend building, myself two, flowering lights, to go either side of a 400 watt M Halide/sodium light.
Each light will be built of 60 Red 10 Blue 3 watt high power Leds.
with this set up I will be trying to see how much I can grow in, I'm hoping for over 2.5 square meters, but well see.
I see lots of talk out there and poeple trying to flower 2 Square Metres, of 3 foot high plants with 250 0r 500 so called high intensity LED panels, two foot from the plants and then they wonder why it turns out crap.
Granted this is still in its infancy, and to buy built up lamps is still very expensive, anything remotely powerfull anyway.
But they are getting better month by month, and very soon LEDs will be replacing HIDs in lighting applications, street lights even.
The time is now, or very soon Ha Ha Ha.
The plusses especially for weed, are numerous, and soon someone other than NASA, will make it work.
Hope its me!!!!!!!!!!!!
I'll keep you all informed of anything interesting.
Sorry if I went on a bit.
The Martian
Click to expand...
LEDs have surpassed CFL in the lab but this is what is more typical of whay you're going to buy:

DealExtreme: $18.50 10W LED Emitter (11V~12V / 300 Lumens White / 6500K)
Keep in mind that a lot of these luminous efficay quotes are for high power LEDs actually running at 1 mA or so where they are much more efficient.

15 watts LEDs can be bought here:

LedEngin Distributor they accempt small orders.

This is an accurate absortion graph:



My own reflectivity and transmissivity measurements roughly reflect this graph. Some leaves are different, for example, sweet basil and purple basil.

You want to use this graph because it is a measure of total photosythetic activity and not just the absorbtion spikes of various molecules suspended in a solvent. This is a reflection of total carbon intake (CO2) as measured by gaseous oxygen given off the by plant or the dry weight of the biomass.
 
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T

techhead420

Well-Known Member
BTW, just to add to the discussion, here's a few links about the benefits of green light for plants that you all might find interesting.

Green-light supplementation for enhanced lettuce growth under red- and blue-light-emitting diodes.

Green Light Stimulates Early Stem Elongation, Antagonizing Light-Mediated Growth Inhibition

Plants grown under LEDs tend to take longer to ripen. Ripening is largely controlled by a hormone by ethylene. Ethylene production is controlled by another hormone called auxin. Green light has been shown to boost auxin levels. You can see where I'm going with this and the problem with todays LED grow lights. Blue light supresses auxins (this is why we don't use halides for flowering) and green light boosts auxins (HPS has lots of green light in its spectrum). The trick is to find the right balance and this is the HUGE benefits of LEDs to a person like me and other hackers who can now find the optimal ratio, even if they aren't as efficient as other types of ligthing.

The above rant is why we don't need to look just at the total photosynthetic effect, we need to look at the total photomorphogenesis effect. Unfortunately, these people kicking out the LED lights tend to be engineers rather than those trained in photobiology.

If one uses LEDs grow lights I recommend build your own using the 15 watt LEDs in the link above. You need a big heat sink!
 
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The Martian

The Martian

Active Member
Hi All Again.
Respect techhead, your the first person I've come accross to actually talk sense.
and your right I do have an engineering/tech background too.
thats very interesting, I was under the impressinon that green was almost wholely unused, as obviously green light falling on a green surface is mostly/wholely reflected.
I'm in the procces of building a new light or two, to augment a 400 watt sodi, but I'm gonna be using 50 or 60 of the High power 3 watters, in each light, I'm reasearching the colour ratio now, hopefully for my next grow.
but as I undertand it its mainly the red end, with a smaller proportion of blue, to stop them going too legggy, with them either side of a sodium, I'd be expecting the sodium to supply the other wavelegths in abundance, but all the extra red one can give them from LEDs sounds promising.

toodle ooo
 
The Martian

The Martian

Active Member
Hi All
Just a quicky.
Techhead, can you explain why "green light can better penetrate the plant canopy and potentially increase plant growth by increasing photosynthesis from the leaves in the lower canopy". surely intensities being equal the higher power light would penetrate better, (that being towards blue, the higher the frequency the more energy the light carries).
So is it something biological? Biology is obviously one of youir strong suits, and not mine.
also they mention adding 24% green light, "The addition of 24% green light (500 to 600 nm) to red and blue LEDs (RGB treatment) enhanced plant growth.
This is very vague, and 24% is a big proportion to add, for something that is very largely reflected, (if it wasn't it would'nt look green).
Its posibly down to the fact that they did'ny add 24% green light, 500 to 600 nm is from very dark green right up to the end of yellow, almost going orange, very nearly a third the whole visible spectrum. so to say that the extra biomass is down to the addition of green light is an exageration at best, and complete nackers at worst.
 
The Martian

The Martian

Active Member
Hi All, only me again.
Sorry techhead, just got to the second link, is'nt the gist that the addition of green light, helps stem elongation????
BUT is'nt this exactly what we don't want when trying to grow nice dense plants, that support lots of bud?

I'm sorry but you've not convinced me about green light, either side of green maybe.
I need to look into this in more depth.
 
mane2008

mane2008

Well-Known Member
green light wont grow plants i have a green light to go see my plants in da night cycle.
BTW its especially made to go see plants in da dark cycle.
 
T

techhead420

Well-Known Member
mane2008 said:
green light wont grow plants i have a green light to go see my plants in da night cycle.
BTW its especially made to go see plants in da dark cycle.
Click to expand...
You can use a small green light for different reasons unrelated to photosynthesis or auxin production. In this case one can use a small green light because our eyes are most sensitivie to green (efficacy of a 100% efficient monochromatic light source at 555nm would be 683 lumens per watt).

We can also use a small green light source because green photons have a rather small affect on the phytochrome molecule which regulates the plant's photoperiod.

Phytochrome - Wikipedia, the free encyclopedia
 
T

techhead420

Well-Known Member
The Martian said:
Hi All
Just a quicky.
Techhead, can you explain why "green light can better penetrate the plant canopy and potentially increase plant growth by increasing photosynthesis from the leaves in the lower canopy". surely intensities being equal the higher power light would penetrate better, (that being towards blue, the higher the frequency the more energy the light carries).
So is it something biological? Biology is obviously one of youir strong suits, and not mine.
also they mention adding 24% green light, "The addition of 24% green light (500 to 600 nm) to red and blue LEDs (RGB treatment) enhanced plant growth.
This is very vague, and 24% is a big proportion to add, for something that is very largely reflected, (if it wasn't it would'nt look green).
Its posibly down to the fact that they did'ny add 24% green light, 500 to 600 nm is from very dark green right up to the end of yellow, almost going orange, very nearly a third the whole visible spectrum. so to say that the extra biomass is down to the addition of green light is an exageration at best, and complete nackers at worst.
Click to expand...
You are correct, we don't know how much actual green light was used and it is rather vague that 500-600nm is refered to as green in photo biology. I have done pure green lettuce grows (no stem elongation!) and from my own observations, grren light does have a powerful effect on plant morphology.

You can get more photosynthesis with green light in the lower canopy due to the higher transmissitivity of green light in the leaves. More green than blue light in the lower canopy and will encourage the petiole of the leaves to elongate. This elongation of the petiole is going to stretch the leaves out from under the lower canopy so that they can capture light. This is essentially why plants have evolved a reaction to green light and it all gets down to hormones.

What happens with green light is that it will stimulate an auxin called indole-3-acateic acid. This causes the cell walls to loosen so that they can fill with fluid causing streching. This can cause stem elongation but it can also cause bigger leaves. High amounts of auxins are needed for flowering and this is where the LED grow lights on the market fall short. They use just red and blue, the blue light has the opposite affect on plants and will supress auxins which will cause a delay in ripening in pot plants. My own side by side comparisons do agree with these statements.

We don't want this stem elongation in the veg stage so we use lights with more blue (halides/cool CFL).

Far red (700nm-about 780nm) will have the same affect on plants as green in addition to being useful to tweeking the photo period of a plant due to far red's light influence on the phytochrome molecule.

Plants will actually grow away from green light just like they will grow towards blue light.

Rooting is also controlled by auxins (this is why auxins are refered to a master hormone). Studies have shown the benefits of using far red to add in rooting of some plants (source: "Adventious Rooting in Cuttings" pg 222-223).

I think I'll start a new thread in a few days discussing photomorphogenisis so that people can understand lighting from a photobiology perspective rather than just an engineering perspective.
 
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